Instead, decorated former Detective John Brandt says in a blockbuster new lawsuit, his role as head of security for a well-heeled Manhattan lawyer was nothing but a nightmare — with his boss laying naked in bed in front of him watching porno flicks and shelling out money to a flock of young Latino boys.

“I got to the point where I just couldn’t do it anymore,” Brandt, 43, of Floral Park, LI, told The Post of his time with high-powered lawyer Roy Adams, 70.

Brandt, a retired detective with the NYPD’s elite Major Case Squad, recently sued Adams — who works for the tony firm Constantine Cannon — in federal court in Central Islip for unspecified damages related to his alleged bizarre, 18-month stint as the lawyer’s security chief and driver.

Brandt — who had worked on such high-profile cases as the Imette St. Guillen murder — first met Adams through mutual police pals in the late ’90s.

As Brandt neared his 20-year mark with the NYPD, Adams began to lobby him to retire and work for him, the suit states.

Brandt said Adams promised him the same pay he was receiving as a detective — more than $130,000 annually, according to the lawsuit.

Brandt, a married dad of two, left the force in June 2008 and began working for Adams.

But his optimism began to wane on one of his first assignments — picking up Adams from his Upper East Side apartment and ferrying him to a meeting.

Brandt arrived to find Adams’ apartment walls completely covered with paintings and pictures of nude men, according to the suit. And when the lawyer beckoned Brandt to his room, the ex-cop found his new boss naked in bed watching pornography, the papers state.

As part of his job, Brandt was ordered once a week to bring a large envelope full of cash to a young Latino man in Adams’ apartment, according to his suit. The man would then disperse the dough to a group of about 20 other young Latinos, referred to by Adams as “The Boys,” who would provide “’round-the-clock personal services,” the suit states.

Brandt says in his suit that the payments were drawn from a nonprofit group Adams presided over called the Fund for Children of the Americas that purported to assist orphans in Latin America.

At one point, Adams even started to try to fondle Brandt, the suit says.